Since being adopted by scientists in the mid-1980s, the word ‘biodiversity’ has become a default term for describing nature and its significance. We’re in the midst of a biodiversity crisis; biodiversity loss threatens human well-being; citizen scientists monitor their local biodiversity; and so on. The word is so ubiquitous that its comprehension by the public is taken for granted—yet a great many people don’t even know what it means.

“It seems prudent for communicators to use ‘biodiversity’ cautiously,” write ecologists led by Michael Weston of Australia’s Deakin University in the journal Pacific Conservation Biology. “At the very least, anyone using this term should provide a definition with it.”